You can fill a lineup vs. both a right-handed and left-handed starter.

You have a starting pitcher available for your next game.

Minor Leagues:

You may move anyone from the active roster to the minor leagues at any time, unless they are suspended.

Before your first game of the season, your roster may be set without any penalties.

Any time during the season, any player moved to the minors must stay there for 10 days before they are eligible to return to your active roster unless they are replacing a player that is placed on the DL.

Players may make unlimited trips between the active roster and the minors EXCEPT for players who have a USE percentage, who may not return to the active roster once they have been sent to the minors (see section on Use Percentage players)

Disabled List:

Any injured player can be moved to the disabled list.

Players placed on the DL must stay there for 15-days, retroactive to the day after their injury.

You can have an unlimited number of players on the DL.

Percent Use Players:

Players that have a percentage value listed as their USE value may only be on the active roster for that percentage of the season. So in a 54-game season, a 30% use player can only be on the active roster for 16 games.

Percent Use players MUST serve their time on the active roster contiguously, meaning that once they are sent down to the minors they cannot return to the active roster.

Often Percent Use players were mid or late-season callups.

Use vs RH/LH:

Batters that have values for Use vs RH or vs LH are restricted to a certain number of at-bats against pitchers of the specified throwing arm.

These values are pro-rated for the length of the season you are playing. So in a 54-game season, a player with a use vs RH of 51 can only have 17 AB against right-handed pitchers during the season.

Players with Use values of less than 20 are not eligible to start OR pinch-hit against a pitcher of the specified throwing arm.

Players must have at least 3 AB remaining to start against a pitcher of the specified throwing arm.

Players must have at least 1 AB remaining to pinch-hit against a pitcher of the specified throwing arm.

If you insert a player into the game who has 0 AB remaining against the throwing arm of the current pitcher, you will be forced to remove that player the next time he comes to bat.

Spot Starters:

Pitchers who have a Spot Start value are limited in how many starts they can make.

This value is pro-rated for the length of the season you are playing. So in a 54-game season, a pitcher with a spot-start value of 6 can make 2 starts.

Meta

The following are trademarks or service marks of Major League Baseball entities and may be used only with permission of Major League Baseball Properties, Inc. or the relevant Major League Baseball entity: Major League, Major League Baseball, MLB, the silhouetted batter logo, World Series, National League, American League, Division Series, League Championship Series, All-Star Game, and the names, nicknames, logos, uniform designs, color combinations, and slogans designating the Major League Baseball clubs and entities, and their respective mascots, events and exhibitions.